fix: Update terminology from "Buchungsoption" to "Termin" for clarity and consistency across the site

Website/templates/base.html

@@ -518,7 +518,7 @@
             <div class="nav-links" id="mainNav" aria-label="Main Navigation" aria-hidden="true">
                 <a href="{{ url_for('default') }}">Start</a>
                 <a href="{{ url_for('dienstleistungen') }}">Für Schulen</a>
-                <a href="{{ url_for('appointments') }}">Buchungsoption</a>
+                <a href="{{ url_for('appointments') }}">Termin buchen</a>
                 <a href="{{ url_for('kontakt') }}">Kontakt</a>
                 {% if 'username' in session %}
                     <a class="nav-user-link" href="{{ url_for('my_invoices') }}">Meine Rechnungen</a>
@@ -537,7 +537,7 @@
                 {% endif %}
             </div>
             <div class="nav-actions">
-                <a class="nav-btn primary" href="{{ url_for('appointments') }}">Buchungsoption</a>
+                <a class="nav-btn primary" href="{{ url_for('appointments') }}">Termin buchen</a>
                 {% if 'username' in session %}
                     <details class="nav-dropdown">
                         <summary class="nav-btn">Nutzerbereich</summary>
@@ -598,7 +598,7 @@
                         <li><a href="{{ url_for('dienstleistungen') }}">Leistungsübersicht</a></li>
                         <li><a href="{{ url_for('team') }}">Team</a></li>
                         <li><a href="{{ url_for('blog') }}">Neuigkeiten</a></li>
-                        <li><a href="{{ url_for('appointments') }}">Buchungsoption</a></li>
+                        <li><a href="{{ url_for('appointments') }}">Termin buchen</a></li>
                     </ul>
                 </div>
                 <div class="footer-section">